Hot Book Sale Unauthorized charge. Boca Raton, Florida

I ordered a book from Hot Book Sale and next thing I know there were additional charges on my credit card.  I phoned the 888 number and was told that $19.95 was a monthly membership fee.  I DID NOT sign up for a membership.  As a matter of fact, I made sure I unchecked the box requesting weekly information.  They also charged me $1 for "handling" the membership application.  They didn't give me too hard a time about canceling and refunding the charge.  I am concerned as to how long it will take to see the credit.  Definite rip-off as there was absolutely nothing on the check-out form that committed you to a membership.